US3158532A - Tapered pore filter elements - Google Patents

Tapered pore filter elements Download PDF

Info

Publication number
US3158532A
US3158532A US74130A US7413060A US3158532A US 3158532 A US3158532 A US 3158532A US 74130 A US74130 A US 74130A US 7413060 A US7413060 A US 7413060A US 3158532 A US3158532 A US 3158532A
Authority
US
United States
Prior art keywords
fibers
layer
filter
porous
fluid
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US74130A
Other languages
English (en)
Inventor
David B Pall
Cyril A Keedwell
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Pall Corp
Original Assignee
Pall Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to GB1000038D priority Critical patent/GB1000038A/en
Application filed by Pall Corp filed Critical Pall Corp
Priority to US74130A priority patent/US3158532A/en
Application granted granted Critical
Publication of US3158532A publication Critical patent/US3158532A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D39/00—Filtering material for liquid or gaseous fluids
    • B01D39/14—Other self-supporting filtering material ; Other filtering material
    • B01D39/20—Other self-supporting filtering material ; Other filtering material of inorganic material, e.g. asbestos paper, metallic filtering material of non-woven wires
    • B01D39/2003—Glass or glassy material
    • B01D39/2006—Glass or glassy material the material being particulate
    • B01D39/2013—Glass or glassy material the material being particulate otherwise bonded, e.g. by resins
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D39/00—Filtering material for liquid or gaseous fluids
    • B01D39/14—Other self-supporting filtering material ; Other filtering material
    • B01D39/20—Other self-supporting filtering material ; Other filtering material of inorganic material, e.g. asbestos paper, metallic filtering material of non-woven wires
    • B01D39/2003—Glass or glassy material
    • B01D39/2017—Glass or glassy material the material being filamentary or fibrous
    • B01D39/2024—Glass or glassy material the material being filamentary or fibrous otherwise bonded, e.g. by resins
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D39/00—Filtering material for liquid or gaseous fluids
    • B01D39/14—Other self-supporting filtering material ; Other filtering material
    • B01D39/20—Other self-supporting filtering material ; Other filtering material of inorganic material, e.g. asbestos paper, metallic filtering material of non-woven wires
    • B01D39/2068—Other inorganic materials, e.g. ceramics
    • B01D39/2072—Other inorganic materials, e.g. ceramics the material being particulate or granular
    • B01D39/2079—Other inorganic materials, e.g. ceramics the material being particulate or granular otherwise bonded, e.g. by resins
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D39/00—Filtering material for liquid or gaseous fluids
    • B01D39/14—Other self-supporting filtering material ; Other filtering material
    • B01D39/20—Other self-supporting filtering material ; Other filtering material of inorganic material, e.g. asbestos paper, metallic filtering material of non-woven wires
    • B01D39/2068—Other inorganic materials, e.g. ceramics
    • B01D39/2082—Other inorganic materials, e.g. ceramics the material being filamentary or fibrous
    • B01D39/2089—Other inorganic materials, e.g. ceramics the material being filamentary or fibrous otherwise bonded, e.g. by resins

Definitions

  • This invention relates to porous materials, and particularly nonwoven fibrous materials, especially adapted for use as filter media, and to a process for preparing such materials.
  • the materials comprise mixed particles of different sizes, and are characterized by tapered pores defined by varying the proportion of particles of different sizes from surface to surface of the material.
  • Filter media can generally be classified as being of one of two typesdepth filters and surface filters.
  • a surface filter removes suspended material from the fluid passed through the filter by collecting such material on its surface, and the material thus removed forms a filter cake or bed upon the filter. This material naturally obstructs the openings in the surface of the filter, because the fluid must flow through this material, which thus effectively reduces the diameter of the filter openings to the size of the pores in the filter cake. This reduction in effective diameter of pore openings in the filter increases the pressure differential required to mmntain flow through the filter. As this process continues, the filter eventually becomes clogged, and must be cleaned or replaced. This is a necessary task which occurs with burdensome frequency when large amounts of suspended material must be removed.
  • inert materials have been added to the fluid which serve to maintain a greater proportion of open area in the filter cake.
  • Such materials are called filter aids, and diatomaceous earth is a typical example.
  • Coarser filters capable of removing the coarsest of the suspended material have also been inserted earlier in the fluid line, to remove some of the suspended material before the'main fine pore filter is reached. Neither of these expedients is always practical, and consequently surface filters because of their low dirt capacity are not always practical to meet large scale commercial filtration needs.
  • the filter element In depth filtration, the filter element is designed to remove contaminants not only on the surface of the element but also as the fluid passes through the element, which has a considerable thickness and which has a plurality of pores of distinct length. The length of the pores increases the dirt capacity, because there is more room for dirt along the pores.
  • Most depth filters are made of masses of fibers or other particulate material, held together by mechanical means or by bonding. One or several layers of such materials can be employed, and these layers can vary in porosity, with the coarsest layer usually arranged to first contact the suspended material, thereby removing from the fluid medium first the coarser and then the finer material as it passes through the filter, thus obtaining some distribution of the contaminants through the filter, and obtaining an extended life as compared to a surface filter.
  • porous materials in the form of bats or sheets of any desired thickness having pores which are tapered and capable of continuous variation in diameter and configuration from one surface of the medium to the other.
  • the surface dirt retention eifect characteristic of surface filters and multi-layered depth filters is avoided in the porous materials of the invention, and the entire open volume of the porous material is available to its maximum extent, for a higher dirt capacity, before clogging.
  • particulate material which can be in the form, for example, of fibers or granules of the material of which the porous material is to be composed, is suspended in a fluid and deposited therefrom in the form of a porous layer on and/ or into a base.
  • Particulate material of at least two sizes, each size suspended in fluid systems, separately, are blended together in the desired proportions before laydown on the base, and the desired configmration in pore diameter from surface to surface of the material is obtained by varying the proportion of the multi-size materials in the layer during deposition.
  • the different size particles can be deposited in any proportions and in any order at any point in the layer, so that a porous material can be obtained in which the pores are of any configuration and have a constantly varying diameter.
  • the pore diameter at the surfaces can be large or small, and can increase or decrease in any portion or throughout, as desired.
  • the configuration of the pores depends not only on the choice and concentration of the materials deposited but also on the base or substratum on which the particulate materials are deposited. In general, one or more of three types of bases will be used:
  • a base which remains a part of the porous layer during its useful application and whose filtration characteristics are modified by the penetration and impregnation thereof by particulate material to form an impreg nated ultra-fine filter medium.
  • Exemplary of such bases are a reinforcing screen or supplemental filter, say, of greater strength, or having a greater or lesser porosity, such as a filter paper or plastic membrane, the porous layer furnishing depth-type filtration in conjunction with said supplemental element.
  • a reinforcing screen or supplemental filter say, of greater strength, or having a greater or lesser porosity, such as a filter paper or plastic membrane, the porous layer furnishing depth-type filtration in conjunction with said supplemental element.
  • the process of the invention is applicable to particulate material or any type or size, the only requirement being that the material be capable of being suspended in a fluid, so that the fluid systems can be blended and the blend brought to the base upon which the particulate material is to be deposited.
  • Fibrous material is particularly desirable, because of its versatility. A great variety of diameters of fibers are available, thus making it pos sible to achieve a very large assortment of mixtures of different diameter fibers for making fibrous material of any porosity, arid such fibers can be made of any length, so as to take advantage of the greater cohesiveness of a layer of long fibers, as compared to granular material layers.
  • Typical fibrous materials include glass, asbestos, potassium titanate, aluminum silicate, mineral wool, regenerated cellulose, polyvinyl chloride, polyvinylidene chloride, polyacrylonitrile, polyethylene, polypropylene, rubber, polymers of *terephthalic acid and ethylene glycol, polyamides, casein fibers, zein fibers, cellulose acetate, viscose rayon, hemp, jute, linen, cot-ten, silk, wool, mohair, paper, and metallic fibers.
  • Particulate materials such as diatomaceous earth, fullers earth, silicon, magnesia, silica, talc, silica gel, alumina, quartz, carbon, activated carbon, clays, synthetic resins and cellulose derivatives, such as polyethylene, polystyrene, olypropylene, urea-formaldehyde, phenol-formaldehyde, polytetra fiuorethylene, polytrifluorochloroethylene, polymers of terephthalic acid and ethylene glycol, polyacrylonitrile, ethyl cellulose, polyamides, and cellulose acetate-propionate, and metal particles such as aluminum, iron, copper, nickel, chromium, and titanium and metal alloys of all kinds, such as monel, brass, stainless steel, bronze, Inconel, cupronickel, Hastelloy, beryllium, and copper can also be employed. Combinations of fibers and particles are also useful, such as combinations of diatornaceous earth and glass fibers.
  • the fluid medium used for the suspension is preferably inert to the particulate material. It should not dissolve a substantial amount thereof, although if the fluid is reused, the fact that some material is in solution is not a disadvantage, since a saturated solution is quickly formed ab initio.
  • the fluid should be volatile at a reasonably elevated temperature below the melting point of the material to facilitate removal after the suspension is laid down. However, nonvolatile fluids may be desirable under certain conditions, and those can be removed, as is more fully described later, by washing out with a volatile solvent that is a solvent for the fluid but not for the particulate material.
  • the fiuid can be the liquid to be filtered by the layer.
  • Typical fluids are water, polyalkylene glycols, such as polyethylene glycols, poly 1,2-propylene glycols, and mono and di alkyl others thereof, such as the methyl,
  • ethyl, butyl and propyl mono and di ethers ethyl, butyl and propyl mono and di ethers, mineral lubricating oils, vegetable oils, and organic solvents such as xylene and petroleum ethers. Since the layer is potentially useful to filter any liquid, depending upon the choice of particulate material, obviously a wide selection of fluids is available, and such would be known to one skilled in this art.
  • a dispersing agent can be incorporated therein.
  • the compression and hence bulk density of the layer can be varied by varying the differential pressure across the layer during laydown.
  • the diilerential pressure is in turn dependent upon fluid velocity and viscosity, and the permeability of the layer.
  • the layers density can be decreased by including a small amount of bulked or crimped coarse particles which can support the finer particles, and space them better, to avoid reducing the average pore size of the layer.
  • pore size and pore configuration are best adjusted by appropriate adjustment in the proportions of multi-size particles and their mean diameter.
  • mean diameter is given to particulate materials consistent in diameter, having only a slight variation each side of the mean, or having a considerable spread, usually, however, not in excess of a factor of 1 to 10, between maximum and minimum diameters above and below the mean diameter.
  • the mean diameter of the particles (2) The shape of the particles (3) The length of the particles (particularly fibers) (4) The distance between adjacent particles Unless an arbitrary external force is applied during laydown, the last depends upon the first three, so that these can be said generally to control mean pore size under any given laydown conditions.
  • fine and coarse fibers may be combined and blended to produce a layer having an intermediate mean pore diameter dependent on the proportions of these fibers.
  • the ratio of mean fiber diameter and length should not exceed a certain value, to ensure that the finer fibers are held in place by the more rigid matrix of coarser fibers during a flow of fiuid through the layer.
  • a layer formed by blending fibers A and B is produced by varying the proportions of fibers A and B at various points in the mat.
  • one side of the mat consists of 100% A fibers, and the other side of 100% B fibers.
  • the mean pore would in effect he tapered. If the mean pore is envisioned as being straight, with straight tapered sides, the variation in mean pore diameter is said to be linear. It the sides of the taper are curved, the variation in mean pore diameter is nonlinear. It will be appreciated that an infinite number of linear and nonlinear configurations are available, by using various combinations of different size and length fibers.
  • FIGURE 1 is a flow chart showing the various steps of the process of the invention.
  • Slurries or suspensions of particulate material of diiferent sizes to be blended are held in separate reservoirs of which only two, A and B, are shown, as exemplary.
  • the slurries are blended together in varying proportions by the pump P, according to the size pores desired at any particular point in the deposited layer.
  • the suspended particulate material in the reservoirs can be held constant but not necessarily alike, in which event the proportions of material are varied at the point of blending quite simply, by varying the rate of introduction of the slurries in the blend.
  • the rate of introduction of the slurries can be kept constant, and the concentrations of suspended material in each reservoir varied as required, but this is more difiicult to do. It is practical to do this when the particulate material can be handled by a solids feeder.
  • the combined mixture of particulate material is then fed to the base upon or into which the layer is to be.
  • This base necessarily has .a porous structure which should be fine enough to retain the smallest particles first deposited, so that these particles are separated from the fluid as it passes through. Normally, the base support much finer particles than its pore diameter. Hence, bases as coarse as a 200 mesh screen may be used to support glass fibers of the order of 1 micron in diameter. If the base is to form an integral part of the porous layer, it is of course removed with the layer when deposition is complete. Any base can be employed, such as :a metal screen, or perforated sheet, or cloth, paper or membrane. Also, the base can be itself a laid-down structure formed upon a base.
  • the base can be in any physical form or configuration, such as a flat sheet, a convoluted or corrugated sheet, or a cylinder of either of these, such as a filter unit or assembly including any of these as a filter element.
  • a bonding agent or binder for bonding the particulate material in the deposited layer.
  • binders are called beater addition binders in the paper industry.
  • the bonding agent or binder may be flowed through the deposited layer as a final operation.
  • the binder can also be incorporated in the layer after lay-down, if it has a deleterious efiect upon the slurry. It can for example be washed through the layer after the fluid has been drawn oil.
  • Any type of adhesive or binder can be employed; it must, of course, be dispersible in the fluid.
  • Many useful binders are known in nonwoven fabric art. Thermosetting binders requiring heating or ageing to effeet a cure can be incorporated, and in this case provision is made for curing the binder in situ after deposition.
  • thermoplastic binders include polyethylene, polypropylene, polymethylene, polyisobutylene, cellulose acetate, ethyl cellulose, copolymers of vinyl chloride and vinyl acetate, polyvinyl chloride, polyvinylidiene chloride, polyvinyl butyral, polyacrylic resins, such as polymethyl methacrylate, alkyd resins, and synthetic rubbers such as butadienestyrene polymers.
  • Thermosetting binders that can be used include phenoldormaldehyde resins, urea-formaldehyde resins, melamine-formaldehyde resins, polyester resins, and epoxy resins, such as polymers of ethylene chlorohydrin and bisphenol A.
  • Binders which are used in solution form to apply them to the layer include any of the above and also polytetrafluoroethylene, polytrifluorochloroethylene, lignin sulionate resins, starch binders, casein binders, and terpene resins.
  • the percentage of large particles may vary uniformly from 0 to 100 from one surface to the other of the layer, and the percentage of small particles varies inversely from 100 to O.
  • the percentages may vary nonuniformly from 0 to 100 and 100 to 0, so that an increased percentage of fine or coarse particles is ob tained in a given part of the layer.
  • FIGURE 2 shows the distribution of particles, for
  • fibers in terms of the ratio of fine fibers to total fibers, when the rates of feed of the two fiber slurries are varied uniformly and continuously from 0 to for fine fibers and from 100 to 0 for coarse fibers.
  • the family of curves show the distribution of fibers when the percentage of fine fibers ranges from 50% to 20%, i.e., when R ranges from 0.5 to 0.2.
  • FIGURE 3 shows the distribution offibers when the rates of feed of the two fiber s-lurries are varied in an arbitrary and nonuniform manner but continuously from O to 100 for fine fibers and from 100 to 0 for coarse fibers, and for percentages of fine fibers ranging from 50% to 26% i.e., when R ranges from 0.5 to 0.2.
  • FIGURE 4 shows a further variation, the principle of which may be applied to linear or nonlinear distribution of fibers.
  • a nonlinear pore is formed having a very large ratio of maximum to minimum mean pore diameter. This is obtained by using three dispersions of three sizes of fibers A, B and C, so that A, fine asbestos fibers, is blended during deposition with fiber B, 1.2 micron mean diameter glass fibers. During deposition the percentage of A in the blend decreases until the deposited slurry consists entirely of B fibers. At or even before this point, the largest fibers C are introduced in a gradually increasing percentage. The resultant eifect is a medium ranging from fine fiber A to coarse fiber C, having an intermediate fiber B to bridge the great dilterence between the diameters of A and C.
  • FIGURE 5 illustrates an apparatus for depositing either linear or nonlinear layers as desired.
  • the apparatus comprises two reservoirs, 1 and 2, one for each size of particle to be blended.
  • 1 is employed for the slurry of small particles, such as fine fibers
  • 2 for the slurry of large particles, such as coarse fibers.
  • the slurries are maintained uniform by the stirrers 3 and 4.
  • a line 5 is provided for delivering slurry from reservoir l to a pump 6, and a similar line 7 is provided in conjunction with reservoir 2 for delivery of slurry to pump 8.
  • the pumps 6 and 8 respectively, deliver the slurries through lines 9 and lit to blending point 11, whence the blend is delivered through line 12 to the base to be covered.
  • the rate of feed of the slurries from the reservoirs 1 and 2 and through pumps 6 and 8 is controlled by regulating thespeed of these pumps. This is accomplished by a pair of earns 15 and 16.
  • the rise and fall of these cams causes the output of these pumps to vary in relation to each other.
  • the shape of the cams controls the rate of change of proportioning of the blend, and determines whether it is uniform or nonuniform.
  • the cams are rotated by the cam input motor 17 via the variable speed gear 18, and the motion of the cams is transmitted by the cam followers 19 and Eli and the speed control shafts 21 and 22 through the variable speed gears 23 and 24 to the pumps 6 and 8.
  • the variable speed gears 23 and 24 are operated by the pump motors 25 and 26.
  • the layer After the layer has been completely formed, it may be desirable to remove therefrom substantially all or a part of the fluid medium of the slurry. This is indicated, for example, if the layer is to be impregnated with a binder.
  • the fluid is sufiiciently volatile, it can be removed by drawing warm or hot air through the layer by application of a differential pressure across the layer, in the same manner as that by which the layer is formed.
  • a nonvolatile liquid can be removed by washing it out with a volatile solvent and then removing the solvent in this Way.
  • a curing oven can be provided, through which the base is passed after the layer is laid down. The layer is then also dried in this oven.
  • wash fluid such as Water, if necessary.
  • Test flow rate 8 gallons per minute per square foot of area.
  • Contaminant Standardized AC fine test dust having the following particle size distribution:
  • EXAMPLE 1 Two separate dispersions of glass fibers were prepared in Mil-H4606 hydraulic flu d, a petroleum base hydraulic fluid, one fiber having a mean diameter of 0.35 micron, the other having a mean diameter of 3.5 microns. These were deposited on a 3 micron nitrocellulose membrane to form a porous layer so that the fibers adjacent to the membrane were composed entirely of 0.35 micron mean diameter fibers while the top surface was composed entirely of 3.2 micron fibers. The fiber distribution in between was as shown in FIGURE 2, so that the overall ratio R of fine fibers to total fibers (by weight) was 0.25, and the deposition weight was 34 grams per square foot.
  • Example 1 was repeated, substituting two fibers Whose average diameters were 1.2 and 10 microns, respectively. These were deposited on the same base as in Example 1 with a fiber distribution as shown in FIGURE 3, so that the overall ratio R of fine fibers to total fibers (by Weight) was 0.33 and the deposition weight was grams per square foot.
  • EXAMPLE 3 Three dispersions were prepared using MlLH-5606 hydraulic fluid, one containing 1.2 micron mean diameter glass fibers, another containing 3.5 micron mean diameter glass fibers and the third containing diatomaceous earth. These materials were deposited on the same base as in Example 1 with a fiber distribution as shown in FIGURE 2, so that the overall ratio R of weight of 1.2 micron fibers to total fiber weight was 0.25 and the fiber deposition weight was 46 grams per square foot. The diatornaceous earth was deposited in direct proportion and simultaneously with the 1.2 micron fibers, so that the ratio R of diatomaceous earth to combined total weight of diatomaceous earth plus weight of 1.2 micron fibers was 0.33.
  • Example 1 was repeated substituting the fibers named in the table which follows. These were deposited on the same base as Example 1, so that the Rratio was as in-.
  • EXAMPLE 18 Two separate dispersions of asbestos fibers were prepared in water, one fiber having a Quebec test value (Manual of Testing Procedures for Chrysotile Asbestos Fibre, Asbestos Textile Institute, pp. 36-40) of O D-0 16, the other having a Quebec test value of 00-12-4. These were deposited on a cotton fiber filter paper to form a porous layer'so that the fibers laid down first were composed entirely of 0-0-12-4 fibers while the top was composed entirely of 00016 fibers. The fiber distribution in between was of the type shown in FIGURE 2, so that the overall ratio R of coarse fibers to total fibers (by weight) was 0.062, and the deposition weight was 9 grams per square foot.
  • the porous layers of the invention are useful as filters for separating solid particles from liquids and gases, as coalescers for separating suspended droplets in fluid media, as agglomerators for separating fluids entrained in gases, as gas diffusers, as dialyzing membranes, and as porous separators in all types of apparatus employing fluids for any purpose, such as separators in batteries and diaphragm cells. They can be made to have a wide range of porosities, to meet any need. The pores can for example be made small enough to remove bacteria and like minute organisms. They can be used as shock absorbers, molded cushioning, acoustical absorbers, and in heat and sound insulation.
  • a process for preparing porous depth filters having pores which vary in diameter and configuration from surface to surface of the material comprising blending continuously at least two separate suspensions comprising particulate material suspended in a fluid, the separate different sizes while varying the proportions blended of particulate material of each size sequentially, and depositing the mixture thus produced upon a base to form a porous material, thereby producing a material having a pore diameter and pore configuration varying from surface to surface thereof.
  • one of the particulate materials is a fibrous material, and another of the particulate materials a granular material.
  • a porous depth filter prepared in accordance with the process of claim 1 and comprising particulate material of at least two sizes blended together in varying proportions from surface to surface, thereby defining pores varying in diameter and configuration and extending from surface to surface of the material.
  • a porous depth filter in accordancewith claim 14 having a base of porous material attached thereto.
  • a porous depth filter in accordance with claim 14 having a base of porous material imbedded therein.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Filtering Materials (AREA)
  • Cell Separators (AREA)
US74130A 1960-12-06 1960-12-06 Tapered pore filter elements Expired - Lifetime US3158532A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB1000038D GB1000038A (enrdf_load_stackoverflow) 1960-12-06
US74130A US3158532A (en) 1960-12-06 1960-12-06 Tapered pore filter elements

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US74130A US3158532A (en) 1960-12-06 1960-12-06 Tapered pore filter elements

Publications (1)

Publication Number Publication Date
US3158532A true US3158532A (en) 1964-11-24

Family

ID=22117897

Family Applications (1)

Application Number Title Priority Date Filing Date
US74130A Expired - Lifetime US3158532A (en) 1960-12-06 1960-12-06 Tapered pore filter elements

Country Status (2)

Country Link
US (1) US3158532A (enrdf_load_stackoverflow)
GB (1) GB1000038A (enrdf_load_stackoverflow)

Cited By (98)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3386231A (en) * 1966-12-23 1968-06-04 American Air Filter Co Pocket-type filter
US3407252A (en) * 1967-05-11 1968-10-22 Pall Corp Process for preparing filters having a microporous layer attached thereto
US3418203A (en) * 1965-09-07 1968-12-24 Owens Illinois Inc Process of forming water-laid products of cellulosic fibers and glass fiber containing ligno-sulfonic acid and sodium silicate and products thereof
US3469057A (en) * 1965-02-15 1969-09-23 Owens Corning Fiberglass Corp Filter system for particulate matter
US3496102A (en) * 1967-11-13 1970-02-17 Du Pont Chromatographic analysis method
US3591010A (en) * 1968-06-10 1971-07-06 Pall Corp Filter having a microporous layer attached thereto
US3595487A (en) * 1968-04-08 1971-07-27 Howard Bidwell Method of automating the operation of paper stock preparation processing apparatus
US3622446A (en) * 1968-01-31 1971-11-23 Keyes Fibre Co Method of making a pocket-type filter and product
FR2215994A1 (en) * 1973-02-01 1974-08-30 Ghh Basel Ag Combined microfilter and fibre depth filter - provides inexpensive water purification on small scale for villages or single houses
FR2216377A1 (en) * 1973-02-01 1974-08-30 Ghh Basel Ag Filtration felt for liq. purificn. - with sheet of coarse fibres backed by network of fine fibres
DE2422426A1 (de) * 1973-05-09 1974-11-28 Amf Inc Verfahren zur behandlung von filtermaterial mit grossen oberflaechenbereichen
US3960650A (en) * 1975-01-13 1976-06-01 Brunswick Corporation Machine and method for making a laminate structure
US3996141A (en) * 1971-10-22 1976-12-07 Wisconsin Alumni Research Foundation Dialysis membrane
US4018646A (en) * 1973-05-09 1977-04-19 Johnson & Johnson Nonwoven fabric
US4058456A (en) * 1976-12-24 1977-11-15 Whatman Reeve Angel Limited External supported filter
US4060488A (en) * 1975-11-20 1977-11-29 E. I. Du Pont De Nemours And Company Particulate membrane ultrafiltration device
US4062818A (en) * 1975-03-21 1977-12-13 International Paper Company Composition for imparting flame resistance and water repellency to textiles
US4066556A (en) * 1976-10-28 1978-01-03 Johnson & Johnson Fluid filter and method of making same
US4073732A (en) * 1974-04-19 1978-02-14 Johnson & Johnson Media for filtering blood
US4105561A (en) * 1974-02-16 1978-08-08 Domnick Hunter Engineers Limited Directional filter
US4119543A (en) * 1976-06-01 1978-10-10 Hollingsworth & Vose Company Filter medium and method of making same
US4129500A (en) * 1973-11-05 1978-12-12 Foseco International Limited Treatment of droplet dispersions
US4170056A (en) * 1976-03-25 1979-10-09 Baxter Travenol Laboratories, Inc. Blood filter
WO1979001147A1 (en) * 1978-05-30 1979-12-27 D Deutsch A microporous member with interconnected,oriented tapered voids
DE2910289A1 (de) * 1979-03-01 1980-09-25 Amf Inc Blattfoermiges filtermedium
DE3010581A1 (de) * 1979-04-06 1980-10-16 Amf Inc Filter und verfahren zu seiner herstellung
DE3028926A1 (de) * 1979-07-30 1981-02-19 Amf Inc Gewickeltes einsatzfilter
US4261832A (en) * 1976-06-02 1981-04-14 Bergwerksverband Gmbh Membranes with preselected pore types for separation processes
US4321288A (en) * 1973-05-09 1982-03-23 Amf Incorporated Process of making an improved filter media
US4419166A (en) * 1978-07-06 1983-12-06 I-Temp Corporation Method of assembling a filter holder
EP0099586A3 (en) * 1982-07-23 1984-03-28 Amf Incorporated Fibrous media containing millimicron-sized particulates
US4507204A (en) * 1979-02-12 1985-03-26 Japan Exlan Company Limited Water-removing material usable for hydrophobic liquids and process for producing the same
DE3403738A1 (de) * 1984-02-03 1985-08-08 Helmut 7074 Mögglingen Schafft Verfahren zum herstellen eines filterkoerpers sowie nach diesem verfahren hergestellter filterkoerper und seine anwendung zum filtrieren und/oder chemisch-physikalischen behandeln von fluessigen und/oder gasfoermigen medien
US4576716A (en) * 1980-12-27 1986-03-18 Unitika, Ltd. Method of producing water treatment medium and medium produced thereby
US4594202A (en) * 1984-01-06 1986-06-10 Pall Corporation Method of making cylindrical fibrous filter structures
US4608173A (en) * 1981-12-11 1986-08-26 Toa Nenryo Kogyo Kabushiki Kaisha Filter
EP0098534B1 (en) * 1982-07-01 1986-09-10 Millipore Corporation Filter apparatus
US4617124A (en) * 1982-07-13 1986-10-14 Pall Corporation Polymeric microfibrous filter sheet, preparation and use
US4618401A (en) * 1982-02-02 1986-10-21 Texon, Inc. Battery separator material
US4629563A (en) * 1980-03-14 1986-12-16 Brunswick Corporation Asymmetric membranes
US4629569A (en) * 1983-05-06 1986-12-16 Gimbel Rolf D Process and device for the separation of impurities from liquids
US4673504A (en) * 1980-10-27 1987-06-16 Cuno Inc. Charge modified microporous membrane
US4708803A (en) * 1980-10-27 1987-11-24 Cuno Incorporated Liquid filtration using hydrophilic cationic isotropic microporous nylon membrane
US4710298A (en) * 1984-04-24 1987-12-01 Sanyo Chemical Industries, Ltd. Auxiliary for dewatering of sludge
US4711793A (en) * 1980-10-27 1987-12-08 Cuno Incorporated Process for charge modifying a microphorous membrane
US4724207A (en) * 1984-02-02 1988-02-09 Cuno Incorporated Modified siliceous chromatographic supports
US4726901A (en) * 1984-01-06 1988-02-23 Pall Corporation Cylindrical fibrous structures with graded pore size
US4734192A (en) * 1982-07-01 1988-03-29 Millipore Corporation Multiwell membrane filtration apparatus
US4737291A (en) * 1981-05-29 1988-04-12 Cuno Incorporated Charge modified microporous membrane
US4743418A (en) * 1981-05-29 1988-05-10 Cuno Incorporated Process for charge modifying a microporous membrane
US4765812A (en) * 1987-10-30 1988-08-23 Allied-Signal Inc. Air laid filtering material
US4781873A (en) * 1985-03-28 1988-11-01 Memtec Limited Reversed phase membranes
US4818340A (en) * 1982-07-15 1989-04-04 Nihon Muki Kabushiki Kaisha Envelope type separator for storage battery and manufacturing process therefor
US4902433A (en) * 1981-11-13 1990-02-20 The British Petroleum Company P.L.C. Equipment and method for filtration using a fabric of polyacrylonitrile fibers
US4904520A (en) * 1988-10-17 1990-02-27 Hercules Incorporated Gas-permeable, liquid-impermeable nonwoven material
US4983288A (en) * 1988-06-03 1991-01-08 Seitz-Filter-Werke Theo & Geo Seitz Gmbh Und Co. Filter element with membrane-type filter material
US4994238A (en) * 1988-06-09 1991-02-19 Daffern George M Constant volume chemical analysis test device
US5055314A (en) * 1989-04-06 1991-10-08 Unilever Patent Holdings Bv Filter aide coating for use in alcoholic beverages
US5098566A (en) * 1986-05-05 1992-03-24 Syrinx Research Institute Pty. Limited Osmotic distillation process and semipermeable barriers therefor
US5114537A (en) * 1990-10-23 1992-05-19 Bio Associates, A California Partnership Dry sheet-like filtering material for liquid depth filtration
US5130025A (en) * 1978-04-20 1992-07-14 Unisearch Limited Membrane separation and purification of compounds
US5133835A (en) * 1990-03-05 1992-07-28 International Paper Company Printable, high-strength, tear-resistant nonwoven material and related method of manufacture
DE4105613A1 (de) * 1991-02-22 1992-08-27 Seitz Filter Werke Verfahren und vorrichtung zur herstellung eines filtervlieses mit unterschiedlichen filtriereigenschaften insbesondere filtervliese fuer wickelkerzen
US5149360A (en) * 1989-07-28 1992-09-22 Pall Corporation Liquid laydown process and metal filter
WO1992017265A1 (en) * 1991-03-26 1992-10-15 Memtec America Corporation Ultraporous and microporous membranes and method of making membranes
US5167820A (en) * 1986-03-24 1992-12-01 Ensci, Inc. Porous membranes and methods for using same
US5188734A (en) * 1991-03-26 1993-02-23 Memtec America Corporation Ultraporous and microporous integral membranes
US5403444A (en) * 1990-03-05 1995-04-04 International Paper Company Printable, high-strength, tear-resistant nonwoven material and related method of manufacture
US5543045A (en) * 1992-09-25 1996-08-06 Dainichiseika Color & Chemicals Mfg. Co., Ltd. Charge mosaic membrane and production process thereof
US5664628A (en) * 1993-05-25 1997-09-09 Pall Corporation Filter for subterranean wells
WO2000012194A1 (en) * 1998-08-27 2000-03-09 Koslow Technologies Corporation Composite filter medium and fluid filters containing same
US6099734A (en) * 1998-07-08 2000-08-08 Baxter International Inc. Apparatus, membranes and methods for removing organic compounds from a biological fluid
US6171443B1 (en) 1990-03-05 2001-01-09 Polyweave International, Llc Recyclable polymeric synthetic paper and method for its manufacture
US6242127B1 (en) 1999-08-06 2001-06-05 Microporous Products, L.P. Polyethylene separator for energy storage cell
US6267252B1 (en) 1999-12-08 2001-07-31 Kimberly-Clark Worldwide, Inc. Fine particle filtration medium including an airlaid composite
US6458491B1 (en) 2000-09-15 2002-10-01 Microporous Products, Lp Separator for energy storage cells
US6485813B1 (en) 1997-03-07 2002-11-26 Koslow Technologies Corp. Method of stabilizing composite media and media produced thereby
US20030080043A1 (en) * 2001-10-30 2003-05-01 Naren Renganath Filter cell design
US6576182B1 (en) * 1995-03-31 2003-06-10 Institut Fuer Neue Materialien Gemeinnuetzige Gmbh Process for producing shrinkage-matched ceramic composites
US20030213742A1 (en) * 2001-04-27 2003-11-20 Decoste David Filter cartrdiges and methods of manufacturing same
US20040118766A1 (en) * 2000-02-03 2004-06-24 Pulek John L. Graded particle-size retention filter medium for cell-type filter unit
US6899834B2 (en) 1998-07-08 2005-05-31 Baxter International Inc. Composite membranes and methods for making such membranes
WO2005099940A1 (en) * 2004-04-15 2005-10-27 Nv Bekaert Sa Method of manufacturing of a sintered metal fiber medium
EP1439897A4 (en) * 2001-10-11 2006-03-08 Aviva Biosciences Corp METHODS, COMPOSITIONS, AND AUTOMATED SYSTEMS FOR SEPARATING RARE CELLS FROM FLUID SAMPLES
US20060273008A1 (en) * 2001-11-02 2006-12-07 Phillips Michael W Membrane adsorber device
US7178676B2 (en) 1998-08-17 2007-02-20 3M Innovative Properties Company Graded particle-size retention filter medium for fluid filtration unit with improved edge seal
US20080050591A1 (en) * 2004-04-15 2008-02-28 Nv Bekaert Sa Method to Manufacture a Non Sintered Metal Fiber Medium
US20080308483A1 (en) * 1999-11-23 2008-12-18 Pall Corporation Fluid treatment elements
EP2050490A1 (de) * 2007-10-18 2009-04-22 Sulzer Chemtech AG Abscheidevorrichtung für Tropfen
US20100071327A1 (en) * 2008-09-24 2010-03-25 Glenn David Alexander Flame Resistant Viscose Filter Apparatus and Method
US20100071326A1 (en) * 2008-09-24 2010-03-25 Glenn David Alexander Flame Resistant Filter Apparatus and Method
US8652241B2 (en) 2008-09-24 2014-02-18 Ellis Fibre Usa Grease removal apparatus, systems and methods
US20150013285A1 (en) * 2011-10-11 2015-01-15 Mahle International Gmbh Filter material
US9290812B2 (en) 2001-10-11 2016-03-22 Aviva Biosciences Corporation Methods and compositions for separating rare cells from fluid samples
EP2346590B1 (en) 2008-11-07 2016-08-10 Hollingsworth & Vose Company Multi-phase filter medium
US9895637B2 (en) * 2010-03-12 2018-02-20 Mann+Hummel Gmbh Filter medium of a filter element, filter element and method for producing a filter medium
US20200094509A1 (en) * 2018-09-21 2020-03-26 Changzhou City Cheng Xin Environmental Protection Technology Co., Ltd. Method for Manufacturing Fibrous Paper-plastic Disc-shaped Product
US11434068B2 (en) 2008-09-24 2022-09-06 Restaurant Technologies, Inc. Flame resistant filter apparatus and method

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE7809355L (sv) * 1978-09-05 1980-03-06 Turex Agenturer Fa Sett och anordning for filtrering
CN114673025B (zh) 2016-06-01 2023-12-05 艺康美国股份有限公司 用于在高电荷需求系统中造纸的高效强度方案

Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1672988A (en) * 1922-04-12 1928-06-12 Raybestos Co Plied sheet and method of producing the same
US1921504A (en) * 1928-04-27 1933-08-08 Brown Co Composite web and method of making the same
US2371313A (en) * 1941-04-15 1945-03-13 Glenn L Martin Co Process for making plastic products
US2372437A (en) * 1943-06-26 1945-03-27 Claude R Wickard Filter medium
US2414833A (en) * 1944-05-09 1947-01-28 C H Dexter & Sons Inc Thermoplastic paper and process of preparing the same
US2503454A (en) * 1944-12-09 1950-04-11 Johns Manville Roofing felt
US2517753A (en) * 1945-11-15 1950-08-08 Johns Manville Microporous sheet and method of manufacture
US2539768A (en) * 1947-05-05 1951-01-30 Cuno Eng Corp Filter element and method of making the same
US2698972A (en) * 1952-08-19 1955-01-11 Lawrence M Keeler Method of assembling textile fibers hydraulically
US2708982A (en) * 1947-07-08 1955-05-24 Thomas J Mcguff Filter media
US2919211A (en) * 1954-12-30 1959-12-29 Lof Glass Fibers Co Evaporator plate and method of producing the same
US2928765A (en) * 1957-02-11 1960-03-15 C H Dexter & Sons Inc Air filter paper and method of making same
FR1236747A (fr) * 1958-09-24 1960-07-22 Jacksons Millboard & Fibre Com Perfectionnement aux feuilles en fibre
US2971907A (en) * 1955-08-17 1961-02-14 Walter J Smith Filter media and method of making
US3039914A (en) * 1959-07-07 1962-06-19 Little Inc A Process for forming a bonded wetformed web and resulting product

Patent Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1672988A (en) * 1922-04-12 1928-06-12 Raybestos Co Plied sheet and method of producing the same
US1921504A (en) * 1928-04-27 1933-08-08 Brown Co Composite web and method of making the same
US2371313A (en) * 1941-04-15 1945-03-13 Glenn L Martin Co Process for making plastic products
US2372437A (en) * 1943-06-26 1945-03-27 Claude R Wickard Filter medium
US2414833A (en) * 1944-05-09 1947-01-28 C H Dexter & Sons Inc Thermoplastic paper and process of preparing the same
US2503454A (en) * 1944-12-09 1950-04-11 Johns Manville Roofing felt
US2517753A (en) * 1945-11-15 1950-08-08 Johns Manville Microporous sheet and method of manufacture
US2539768A (en) * 1947-05-05 1951-01-30 Cuno Eng Corp Filter element and method of making the same
US2708982A (en) * 1947-07-08 1955-05-24 Thomas J Mcguff Filter media
US2698972A (en) * 1952-08-19 1955-01-11 Lawrence M Keeler Method of assembling textile fibers hydraulically
US2919211A (en) * 1954-12-30 1959-12-29 Lof Glass Fibers Co Evaporator plate and method of producing the same
US2971907A (en) * 1955-08-17 1961-02-14 Walter J Smith Filter media and method of making
US2928765A (en) * 1957-02-11 1960-03-15 C H Dexter & Sons Inc Air filter paper and method of making same
FR1236747A (fr) * 1958-09-24 1960-07-22 Jacksons Millboard & Fibre Com Perfectionnement aux feuilles en fibre
US3039914A (en) * 1959-07-07 1962-06-19 Little Inc A Process for forming a bonded wetformed web and resulting product

Cited By (124)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3469057A (en) * 1965-02-15 1969-09-23 Owens Corning Fiberglass Corp Filter system for particulate matter
US3418203A (en) * 1965-09-07 1968-12-24 Owens Illinois Inc Process of forming water-laid products of cellulosic fibers and glass fiber containing ligno-sulfonic acid and sodium silicate and products thereof
US3386231A (en) * 1966-12-23 1968-06-04 American Air Filter Co Pocket-type filter
US3407252A (en) * 1967-05-11 1968-10-22 Pall Corp Process for preparing filters having a microporous layer attached thereto
US3496102A (en) * 1967-11-13 1970-02-17 Du Pont Chromatographic analysis method
US3622446A (en) * 1968-01-31 1971-11-23 Keyes Fibre Co Method of making a pocket-type filter and product
US3595487A (en) * 1968-04-08 1971-07-27 Howard Bidwell Method of automating the operation of paper stock preparation processing apparatus
US3591010A (en) * 1968-06-10 1971-07-06 Pall Corp Filter having a microporous layer attached thereto
US3996141A (en) * 1971-10-22 1976-12-07 Wisconsin Alumni Research Foundation Dialysis membrane
FR2215994A1 (en) * 1973-02-01 1974-08-30 Ghh Basel Ag Combined microfilter and fibre depth filter - provides inexpensive water purification on small scale for villages or single houses
FR2216377A1 (en) * 1973-02-01 1974-08-30 Ghh Basel Ag Filtration felt for liq. purificn. - with sheet of coarse fibres backed by network of fine fibres
US4007114A (en) * 1973-05-09 1977-02-08 Amf Incorporated Fibrous filter medium and process
US4007113A (en) * 1973-05-09 1977-02-08 Amf Incorporated Particulate filter medium and process
US4321288A (en) * 1973-05-09 1982-03-23 Amf Incorporated Process of making an improved filter media
US4018646A (en) * 1973-05-09 1977-04-19 Johnson & Johnson Nonwoven fabric
DE2422426A1 (de) * 1973-05-09 1974-11-28 Amf Inc Verfahren zur behandlung von filtermaterial mit grossen oberflaechenbereichen
US4129500A (en) * 1973-11-05 1978-12-12 Foseco International Limited Treatment of droplet dispersions
US4105561A (en) * 1974-02-16 1978-08-08 Domnick Hunter Engineers Limited Directional filter
US4073732A (en) * 1974-04-19 1978-02-14 Johnson & Johnson Media for filtering blood
US3960650A (en) * 1975-01-13 1976-06-01 Brunswick Corporation Machine and method for making a laminate structure
US4062818A (en) * 1975-03-21 1977-12-13 International Paper Company Composition for imparting flame resistance and water repellency to textiles
US4060488A (en) * 1975-11-20 1977-11-29 E. I. Du Pont De Nemours And Company Particulate membrane ultrafiltration device
US4170056A (en) * 1976-03-25 1979-10-09 Baxter Travenol Laboratories, Inc. Blood filter
US4161422A (en) * 1976-06-01 1979-07-17 Hollingsworth & Vose Company Filter paper and method of making same
US4119543A (en) * 1976-06-01 1978-10-10 Hollingsworth & Vose Company Filter medium and method of making same
US4261832A (en) * 1976-06-02 1981-04-14 Bergwerksverband Gmbh Membranes with preselected pore types for separation processes
US4066556A (en) * 1976-10-28 1978-01-03 Johnson & Johnson Fluid filter and method of making same
US4058456A (en) * 1976-12-24 1977-11-15 Whatman Reeve Angel Limited External supported filter
US5130025A (en) * 1978-04-20 1992-07-14 Unisearch Limited Membrane separation and purification of compounds
US4280909A (en) * 1978-05-30 1981-07-28 Deutsch Daniel Harold Microporous member with interconnected, oriented tapered voids
WO1979001147A1 (en) * 1978-05-30 1979-12-27 D Deutsch A microporous member with interconnected,oriented tapered voids
US4419166A (en) * 1978-07-06 1983-12-06 I-Temp Corporation Method of assembling a filter holder
US4507204A (en) * 1979-02-12 1985-03-26 Japan Exlan Company Limited Water-removing material usable for hydrophobic liquids and process for producing the same
DE2910289A1 (de) * 1979-03-01 1980-09-25 Amf Inc Blattfoermiges filtermedium
DE3010581A1 (de) * 1979-04-06 1980-10-16 Amf Inc Filter und verfahren zu seiner herstellung
DE3028926A1 (de) * 1979-07-30 1981-02-19 Amf Inc Gewickeltes einsatzfilter
US4629563A (en) * 1980-03-14 1986-12-16 Brunswick Corporation Asymmetric membranes
US4673504A (en) * 1980-10-27 1987-06-16 Cuno Inc. Charge modified microporous membrane
US4711793A (en) * 1980-10-27 1987-12-08 Cuno Incorporated Process for charge modifying a microphorous membrane
US4708803A (en) * 1980-10-27 1987-11-24 Cuno Incorporated Liquid filtration using hydrophilic cationic isotropic microporous nylon membrane
US4576716A (en) * 1980-12-27 1986-03-18 Unitika, Ltd. Method of producing water treatment medium and medium produced thereby
US4743418A (en) * 1981-05-29 1988-05-10 Cuno Incorporated Process for charge modifying a microporous membrane
US4737291A (en) * 1981-05-29 1988-04-12 Cuno Incorporated Charge modified microporous membrane
US4902433A (en) * 1981-11-13 1990-02-20 The British Petroleum Company P.L.C. Equipment and method for filtration using a fabric of polyacrylonitrile fibers
US4608173A (en) * 1981-12-11 1986-08-26 Toa Nenryo Kogyo Kabushiki Kaisha Filter
US4618401A (en) * 1982-02-02 1986-10-21 Texon, Inc. Battery separator material
EP0098534B1 (en) * 1982-07-01 1986-09-10 Millipore Corporation Filter apparatus
US4734192A (en) * 1982-07-01 1988-03-29 Millipore Corporation Multiwell membrane filtration apparatus
US4617124A (en) * 1982-07-13 1986-10-14 Pall Corporation Polymeric microfibrous filter sheet, preparation and use
US4818340A (en) * 1982-07-15 1989-04-04 Nihon Muki Kabushiki Kaisha Envelope type separator for storage battery and manufacturing process therefor
EP0099586A3 (en) * 1982-07-23 1984-03-28 Amf Incorporated Fibrous media containing millimicron-sized particulates
US4629569A (en) * 1983-05-06 1986-12-16 Gimbel Rolf D Process and device for the separation of impurities from liquids
US4594202A (en) * 1984-01-06 1986-06-10 Pall Corporation Method of making cylindrical fibrous filter structures
US4726901A (en) * 1984-01-06 1988-02-23 Pall Corporation Cylindrical fibrous structures with graded pore size
US4724207A (en) * 1984-02-02 1988-02-09 Cuno Incorporated Modified siliceous chromatographic supports
US4925570A (en) * 1984-02-03 1990-05-15 Helmut Schafft Method of filtering
DE3403738A1 (de) * 1984-02-03 1985-08-08 Helmut 7074 Mögglingen Schafft Verfahren zum herstellen eines filterkoerpers sowie nach diesem verfahren hergestellter filterkoerper und seine anwendung zum filtrieren und/oder chemisch-physikalischen behandeln von fluessigen und/oder gasfoermigen medien
US4986913A (en) * 1984-02-03 1991-01-22 Helmut Schafft Filter pad
US4710298A (en) * 1984-04-24 1987-12-01 Sanyo Chemical Industries, Ltd. Auxiliary for dewatering of sludge
US4781873A (en) * 1985-03-28 1988-11-01 Memtec Limited Reversed phase membranes
US4909938A (en) * 1985-03-28 1990-03-20 Memtec Limited Reversed phase membranes
US5167820A (en) * 1986-03-24 1992-12-01 Ensci, Inc. Porous membranes and methods for using same
US5098566A (en) * 1986-05-05 1992-03-24 Syrinx Research Institute Pty. Limited Osmotic distillation process and semipermeable barriers therefor
US4765812A (en) * 1987-10-30 1988-08-23 Allied-Signal Inc. Air laid filtering material
US4983288A (en) * 1988-06-03 1991-01-08 Seitz-Filter-Werke Theo & Geo Seitz Gmbh Und Co. Filter element with membrane-type filter material
US4994238A (en) * 1988-06-09 1991-02-19 Daffern George M Constant volume chemical analysis test device
US4904520A (en) * 1988-10-17 1990-02-27 Hercules Incorporated Gas-permeable, liquid-impermeable nonwoven material
US5055314A (en) * 1989-04-06 1991-10-08 Unilever Patent Holdings Bv Filter aide coating for use in alcoholic beverages
US5149360A (en) * 1989-07-28 1992-09-22 Pall Corporation Liquid laydown process and metal filter
US5403444A (en) * 1990-03-05 1995-04-04 International Paper Company Printable, high-strength, tear-resistant nonwoven material and related method of manufacture
US5133835A (en) * 1990-03-05 1992-07-28 International Paper Company Printable, high-strength, tear-resistant nonwoven material and related method of manufacture
US6171443B1 (en) 1990-03-05 2001-01-09 Polyweave International, Llc Recyclable polymeric synthetic paper and method for its manufacture
US5114537A (en) * 1990-10-23 1992-05-19 Bio Associates, A California Partnership Dry sheet-like filtering material for liquid depth filtration
DE4105613A1 (de) * 1991-02-22 1992-08-27 Seitz Filter Werke Verfahren und vorrichtung zur herstellung eines filtervlieses mit unterschiedlichen filtriereigenschaften insbesondere filtervliese fuer wickelkerzen
US5171445A (en) * 1991-03-26 1992-12-15 Memtec America Corporation Ultraporous and microporous membranes and method of making membranes
US5188734A (en) * 1991-03-26 1993-02-23 Memtec America Corporation Ultraporous and microporous integral membranes
WO1992017265A1 (en) * 1991-03-26 1992-10-15 Memtec America Corporation Ultraporous and microporous membranes and method of making membranes
US5543045A (en) * 1992-09-25 1996-08-06 Dainichiseika Color & Chemicals Mfg. Co., Ltd. Charge mosaic membrane and production process thereof
US5664628A (en) * 1993-05-25 1997-09-09 Pall Corporation Filter for subterranean wells
US5909773A (en) * 1993-05-25 1999-06-08 Pall Corporation Method of repairing a damaged well
US6576182B1 (en) * 1995-03-31 2003-06-10 Institut Fuer Neue Materialien Gemeinnuetzige Gmbh Process for producing shrinkage-matched ceramic composites
US6485813B1 (en) 1997-03-07 2002-11-26 Koslow Technologies Corp. Method of stabilizing composite media and media produced thereby
US6908553B1 (en) * 1998-07-08 2005-06-21 Baxter International Inc. Composite membrane with particulate matter substantially immobilized therein
US6899834B2 (en) 1998-07-08 2005-05-31 Baxter International Inc. Composite membranes and methods for making such membranes
US6099734A (en) * 1998-07-08 2000-08-08 Baxter International Inc. Apparatus, membranes and methods for removing organic compounds from a biological fluid
US7582209B2 (en) 1998-08-17 2009-09-01 3M Innovative Properties Company Graded particle-size retention filter medium for fluid filtration unit with improved edge seal
US20070062859A1 (en) * 1998-08-17 2007-03-22 3M Innovative Properties Company Graded particle-size retention filter medium for fluid filtration unit with improved edge seal
US7178676B2 (en) 1998-08-17 2007-02-20 3M Innovative Properties Company Graded particle-size retention filter medium for fluid filtration unit with improved edge seal
US6550622B2 (en) * 1998-08-27 2003-04-22 Koslow Technologies Corporation Composite filter medium and fluid filters containing same
US20030111404A1 (en) * 1998-08-27 2003-06-19 Koslow Evan E. Composite filter medium and fluid filters containing same
WO2000012194A1 (en) * 1998-08-27 2000-03-09 Koslow Technologies Corporation Composite filter medium and fluid filters containing same
US6797167B2 (en) * 1998-08-27 2004-09-28 Koslow Technologies Corp. Composite filter medium and fluid filters containing same
US6242127B1 (en) 1999-08-06 2001-06-05 Microporous Products, L.P. Polyethylene separator for energy storage cell
US20080308483A1 (en) * 1999-11-23 2008-12-18 Pall Corporation Fluid treatment elements
US20090014378A1 (en) * 1999-11-23 2009-01-15 Pall Corporation Fluid treatment elements
US8206583B2 (en) * 1999-11-23 2012-06-26 Pall Corporation Electrically conductive fluid treatment elements
US8206584B2 (en) * 1999-11-23 2012-06-26 Pall Corporation Electrically conductive fluid treatment elements
US6267252B1 (en) 1999-12-08 2001-07-31 Kimberly-Clark Worldwide, Inc. Fine particle filtration medium including an airlaid composite
US20040118766A1 (en) * 2000-02-03 2004-06-24 Pulek John L. Graded particle-size retention filter medium for cell-type filter unit
US6458491B1 (en) 2000-09-15 2002-10-01 Microporous Products, Lp Separator for energy storage cells
US20030213742A1 (en) * 2001-04-27 2003-11-20 Decoste David Filter cartrdiges and methods of manufacturing same
US9290812B2 (en) 2001-10-11 2016-03-22 Aviva Biosciences Corporation Methods and compositions for separating rare cells from fluid samples
EP1439897A4 (en) * 2001-10-11 2006-03-08 Aviva Biosciences Corp METHODS, COMPOSITIONS, AND AUTOMATED SYSTEMS FOR SEPARATING RARE CELLS FROM FLUID SAMPLES
US20030080043A1 (en) * 2001-10-30 2003-05-01 Naren Renganath Filter cell design
US7281410B2 (en) 2001-11-02 2007-10-16 Millipore Corporation Method for determining an effective peclet number for a membrane adsorber device
US20060273008A1 (en) * 2001-11-02 2006-12-07 Phillips Michael W Membrane adsorber device
US20070202001A1 (en) * 2004-04-15 2007-08-30 Nv Bekaert Sa Method Of Manufacturing Of A Sintered Metal Fiber Medium
CN100522422C (zh) * 2004-04-15 2009-08-05 贝卡尔特股份有限公司 制造烧结金属纤维介质的方法
US20080050591A1 (en) * 2004-04-15 2008-02-28 Nv Bekaert Sa Method to Manufacture a Non Sintered Metal Fiber Medium
WO2005099940A1 (en) * 2004-04-15 2005-10-27 Nv Bekaert Sa Method of manufacturing of a sintered metal fiber medium
EP2050490A1 (de) * 2007-10-18 2009-04-22 Sulzer Chemtech AG Abscheidevorrichtung für Tropfen
US8652241B2 (en) 2008-09-24 2014-02-18 Ellis Fibre Usa Grease removal apparatus, systems and methods
WO2010036783A1 (en) * 2008-09-24 2010-04-01 Clean Systems Llc Flame resistant filter apparatus and method
US20100071326A1 (en) * 2008-09-24 2010-03-25 Glenn David Alexander Flame Resistant Filter Apparatus and Method
US20100071327A1 (en) * 2008-09-24 2010-03-25 Glenn David Alexander Flame Resistant Viscose Filter Apparatus and Method
US9599350B2 (en) 2008-09-24 2017-03-21 Ellis Fibre Usa Flame resistant filter apparatus and method
US10167137B2 (en) 2008-09-24 2019-01-01 Efip Holdings Lp Flame resistant viscose filter apparatus and method
US10300422B2 (en) 2008-09-24 2019-05-28 Efip Holdings Lp Grease removal apparatus, systems and methods
US11434068B2 (en) 2008-09-24 2022-09-06 Restaurant Technologies, Inc. Flame resistant filter apparatus and method
EP2346590B1 (en) 2008-11-07 2016-08-10 Hollingsworth & Vose Company Multi-phase filter medium
US9895637B2 (en) * 2010-03-12 2018-02-20 Mann+Hummel Gmbh Filter medium of a filter element, filter element and method for producing a filter medium
US20150013285A1 (en) * 2011-10-11 2015-01-15 Mahle International Gmbh Filter material
US9592465B2 (en) * 2011-11-10 2017-03-14 Mahle International Gmbh Filter material
US20200094509A1 (en) * 2018-09-21 2020-03-26 Changzhou City Cheng Xin Environmental Protection Technology Co., Ltd. Method for Manufacturing Fibrous Paper-plastic Disc-shaped Product

Also Published As

Publication number Publication date
GB1000038A (enrdf_load_stackoverflow)

Similar Documents

Publication Publication Date Title
US3158532A (en) Tapered pore filter elements
US3238056A (en) Microporous materials and process of making the same
US3353682A (en) Fluid-permeable fibrous multilayer materials and process of making the same
US3573158A (en) Microporous fibrous sheets useful for filters and apparatus and method of forming the same
US4303472A (en) Filter elements for gas or liquid and methods of making such filters
US5766288A (en) Multilayered deep-bed filter material
US3115459A (en) Filter
US2383066A (en) Filter unit and method of making the same
US2539768A (en) Filter element and method of making the same
US3276597A (en) Filter media
US3261473A (en) Glass fiber cartridge filters for drycleaning solvent filtration
EP0417069B1 (en) Air laid filtering material
KR101752922B1 (ko) 다중상 필터 매체
JP6050752B2 (ja) デプスフィルターとサブミクロンフィルターとの組合せを含むカートリッジフィルター並びにｒｏ前処理方法
US4048075A (en) Filter cartridge
US3262578A (en) Glass fiber filter tubes
EP0352888A2 (en) Filtration fabric produced by wet laid process
JPS5953085B2 (ja) 濾材およびその製法
US3407252A (en) Process for preparing filters having a microporous layer attached thereto
US3256997A (en) Apparatus for separating immiscible liquids
JP3138016B2 (ja) 濾 材
SK150896A3 (en) Fibre-coated filter element and process for manufacturing the same
US3053762A (en) Filter material
FI127543B (en) Filtration material and its use
US3831766A (en) Filter media